I've found a new mix that is pretty good - Zach's Spicy Chili Mix:
It's a family company based in La Porte, a suburb of Houston, and apparently has been around a long time. I read about them a few months ago on eGullet.
The packet says it's good for up to 2 pounds of chili but I think it's stretching it to go over 1.5 pounds. Its a very aromatic mix. I've made the best chili with it using 2 packs on about 3 pounds of meat, saving the second packet for a second dump, as the chili competition cooks term it.
I first started finding it in butcher shops. In grocery stores that carry it, it tends to be close to the meat department rather than the spice aisle or the isle with the gravy mixes, etc., where you tend to find Wick Fowler, Carrol Shelby and Shotgun Willie's, etc.
They also sell their mixes in 1 lb. bags; maybe they're really oriented more towards institutional sales. I make a lot of chili but I can't imagine how long it'd take to use up a pound of chili mix. I've paid between $1.27 and $1.34 per packet.
P.S. I think it's a little oversalted. http://www.zachspice.com